Unaudited Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Apr. 01, 2018	Apr. 02, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 5,590	$ 15,994
Other comprehensive income (loss), before tax:
Unrealized gains (losses) on derivative instruments	692	(1,697)
Unrealized losses on available-for-sale securities	(38)	(55)
Other comprehensive income (loss), before tax	654	(1,752)
Tax benefit (provision) related to derivative instruments	(61)	196
Tax benefit (provision) related to available-for-sale securities	(11)	20
Other comprehensive income (loss), net of tax	582	(1,536)
Comprehensive income	$ 6,172	$ 14,458

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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